////#include <iostream>
////#include <map>
////using namespace std;
////int main() {
////    /*int L = 0;
////    int R = 0;
////    size_t ret = 0;
////    cin >> L;
////    cin >> R;
////    int n = L;
////    int f = n;
////    while (n <= R)
//////    {
////        f = n;
////        while (f > 0)
////        {
////            int i = f;
////            i = i % 10;
////            if (2 == i)
////                ret++;
////            f /= 10;
////        }
////        n++;
////    }
////    cout << ret << endl;*/
////    map<int, int> share;
////    while (true)
////        share.emplace(make_pair(1, 1));
////
////}
//#include <iostream>
//#include <string>
//using namespace std;
//
//int main()
//{
//    string s = "absssbc";
//    //cin >> s;
//    string tem;
//    for (auto& e : s)
//    {
//        if (tem.size() == 0)
//        {
//            tem += e;
//            continue;
//        }
//        if (tem.size() != 0)
//        {
//            if (tem.back() != e)
//                tem += e;
//            else
//                tem.erase(tem.find(e));
//        }
//    }
//    if (tem.size() == 0)
//        cout << 0 << endl;
//    else
//        cout << tem << endl;
//    return 0;
//}